The broad long-term objective of the Parent Grant (EB000215) is to improve the quality of fMRI data including improved contrast-to-noise ratio, higher spatial resolution, increase of information content in the experiment, and improved temporal resolution. The Description of Aim 3 from the Parent Grant is as follows: "Most fMRI studies with rats have used anesthesia, and studies on the awake, mechanically immobilized rat can be criticized as placing the animal under too much stress. Both stress and anesthetics are confounding factors. The goal of this aim is to develop methodology, hardware and software to eliminate the necessity of using anesthetics in fMRI research using rats. Technology will be developed at 3T and extended to 9.4T." Using progress that has been made on this Aim, an fMRI model of nerve transfer in a rat is proposed that will be used to investigate cortical plasticity following surgery. In Aim 1, the fMRI stimulus will be delivered by surgically implanted bipolar electrodes on the right musculocutaneous nerve to allow direct nerve stimulation in an fMRI experiment. Two methods for control of the experiment, both using needle electrodes, will be compared: left forepaw interdigital nerve stimulation and left biceps musculo-cutaneous nerve stimulation. In Aim 2, a nerve transfer experiment is designed with C7 nerve transfer to the right brachial plexus. In this Aim, cortical plasticity over time will be observed directly using fMRI. The controls will be the same as for Aim 1. This NIBIB Research Supplement will provide research experience for a clinical resident in plastic surgery that is based on progress that has occurred on Aim 3 of the Parent Grant. Mentoring in this strongly interdisciplinary proposal will be provided by the PI (fMRI Biophysics); Dr. Hani Matloub, Co-Pi, Microsurgeon; Dr. Ji-Geng Van, Co-Mentor, C7 nerve transfer surgery; and Dr. Safwan Jaradeh, Co-Mentor, clinical electrophysiology. The Clinical Resident, Dr. Younghoon R. Cho, has a well articulated goal of a career in academic medicine. This candidate has both MD and PhD degrees. He will receive training in fMRI small animal research, in electrophysiology, and in nerve transfer microsurgery. The proposed research has significant opportunity to enhance knowledge and could well serve as the basis of a research career in medicine. [unreadable] [unreadable] [unreadable]